/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
 *
 * This library is open source and may be redistributed and/or modified under
 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
 * (at your option) any later version.  The full license is in LICENSE file
 * included with this distribution, and on the openscenegraph.org website.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * OpenSceneGraph Public License for more details.
*/

#ifndef OSG_VEC3D
#define OSG_VEC3D 1

//#include <osg/Vec2d>
//#include <osg/Vec3f>
#include <math.h>

namespace osg {

    /** General purpose double triple for use as vertices, vectors and normals.
      * Provides general math operations from addition through to cross products.
      * No support yet added for double * Vec3d - is it necessary?
      * Need to define a non-member non-friend operator*  etc.
      *    Vec3d * double is okay
    */

    class Vec3d
    {
    public:

        /** Data type of vector components.*/
        typedef double value_type;

        /** Number of vector components. */
        enum { num_components = 3 };

        value_type _v[3];

        /** Constructor that sets all components of the vector to zero */
        Vec3d() { _v[0] = 0.0; _v[1] = 0.0; _v[2] = 0.0; }

        //inline Vec3d(const Vec3f& vec) { _v[0] = vec._v[0]; _v[1] = vec._v[1]; _v[2] = vec._v[2]; }

        //inline operator Vec3f() const { return Vec3f(static_cast<float>(_v[0]), static_cast<float>(_v[1]), static_cast<float>(_v[2])); }

        Vec3d(value_type x, value_type y, value_type z) { _v[0] = x; _v[1] = y; _v[2] = z; }
        //Vec3d(const Vec2d& v2, value_type zz)
        //{
        //    _v[0] = v2[0];
        //    _v[1] = v2[1];
        //    _v[2] = zz;
        //}

        inline bool operator == (const Vec3d& v) const { return _v[0] == v._v[0] && _v[1] == v._v[1] && _v[2] == v._v[2]; }

        inline bool operator != (const Vec3d& v) const { return _v[0] != v._v[0] || _v[1] != v._v[1] || _v[2] != v._v[2]; }

        inline bool operator <  (const Vec3d& v) const
        {
            if (_v[0] < v._v[0]) return true;
            else if (_v[0] > v._v[0]) return false;
            else if (_v[1] < v._v[1]) return true;
            else if (_v[1] > v._v[1]) return false;
            else return (_v[2] < v._v[2]);
        }

        inline value_type* ptr() { return _v; }
        inline const value_type* ptr() const { return _v; }

        inline void set(value_type x, value_type y, value_type z)
        {
            _v[0] = x; _v[1] = y; _v[2] = z;
        }

        inline void set(const Vec3d& rhs)
        {
            _v[0] = rhs._v[0]; _v[1] = rhs._v[1]; _v[2] = rhs._v[2];
        }

        inline value_type& operator [] (int i) { return _v[i]; }
        inline value_type operator [] (int i) const { return _v[i]; }

        inline value_type& x() { return _v[0]; }
        inline value_type& y() { return _v[1]; }
        inline value_type& z() { return _v[2]; }

        inline value_type x() const { return _v[0]; }
        inline value_type y() const { return _v[1]; }
        inline value_type z() const { return _v[2]; }

        /** Returns true if all components have values that are not NaN. */
        //inline bool valid() const { return !isNaN(); }
        /** Returns true if at least one component has value NaN. */
        //inline bool isNaN() const { return osg::isNaN(_v[0]) || osg::isNaN(_v[1]) || osg::isNaN(_v[2]); }

        /** Dot product. */
        inline value_type operator * (const Vec3d& rhs) const
        {
            return _v[0] * rhs._v[0] + _v[1] * rhs._v[1] + _v[2] * rhs._v[2];
        }

        /** Cross product. */
        inline const Vec3d operator ^ (const Vec3d& rhs) const
        {
            return Vec3d(_v[1] * rhs._v[2] - _v[2] * rhs._v[1],
                _v[2] * rhs._v[0] - _v[0] * rhs._v[2],
                _v[0] * rhs._v[1] - _v[1] * rhs._v[0]);
        }

        /** Multiply by scalar. */
        inline const Vec3d operator * (value_type rhs) const
        {
            return Vec3d(_v[0] * rhs, _v[1] * rhs, _v[2] * rhs);
        }

        /** Unary multiply by scalar. */
        inline Vec3d& operator *= (value_type rhs)
        {
            _v[0] *= rhs;
            _v[1] *= rhs;
            _v[2] *= rhs;
            return *this;
        }

        /** Divide by scalar. */
        inline const Vec3d operator / (value_type rhs) const
        {
            return Vec3d(_v[0] / rhs, _v[1] / rhs, _v[2] / rhs);
        }

        /** Unary divide by scalar. */
        inline Vec3d& operator /= (value_type rhs)
        {
            _v[0] /= rhs;
            _v[1] /= rhs;
            _v[2] /= rhs;
            return *this;
        }

        /** Binary vector add. */
        inline const Vec3d operator + (const Vec3d& rhs) const
        {
            return Vec3d(_v[0] + rhs._v[0], _v[1] + rhs._v[1], _v[2] + rhs._v[2]);
        }

        /** Unary vector add. Slightly more efficient because no temporary
          * intermediate object.
        */
        inline Vec3d& operator += (const Vec3d& rhs)
        {
            _v[0] += rhs._v[0];
            _v[1] += rhs._v[1];
            _v[2] += rhs._v[2];
            return *this;
        }

        /** Binary vector subtract. */
        inline const Vec3d operator - (const Vec3d& rhs) const
        {
            return Vec3d(_v[0] - rhs._v[0], _v[1] - rhs._v[1], _v[2] - rhs._v[2]);
        }

        /** Unary vector subtract. */
        inline Vec3d& operator -= (const Vec3d& rhs)
        {
            _v[0] -= rhs._v[0];
            _v[1] -= rhs._v[1];
            _v[2] -= rhs._v[2];
            return *this;
        }

        /** Negation operator. Returns the negative of the Vec3d. */
        inline const Vec3d operator - () const
        {
            return Vec3d(-_v[0], -_v[1], -_v[2]);
        }

        /** Length of the vector = sqrt( vec . vec ) */
        inline value_type length() const
        {
            return sqrt(_v[0] * _v[0] + _v[1] * _v[1] + _v[2] * _v[2]);
        }

        /** Length squared of the vector = vec . vec */
        inline value_type length2() const
        {
            return _v[0] * _v[0] + _v[1] * _v[1] + _v[2] * _v[2];
        }

        /** Normalize the vector so that it has length unity.
          * Returns the previous length of the vector.
          * If the vector is zero length, it is left unchanged and zero is returned.
        */
        inline value_type normalize()
        {
            value_type norm = Vec3d::length();
            if (norm > 0.0)
            {
                value_type inv = 1.0 / norm;
                _v[0] *= inv;
                _v[1] *= inv;
                _v[2] *= inv;
            }
            return(norm);
        }

    };    // end of class Vec3d

    /** multiply by vector components. */
    inline Vec3d componentMultiply(const Vec3d& lhs, const Vec3d& rhs)
    {
        return Vec3d(lhs[0] * rhs[0], lhs[1] * rhs[1], lhs[2] * rhs[2]);
    }

    /** divide rhs components by rhs vector components. */
    inline Vec3d componentDivide(const Vec3d& lhs, const Vec3d& rhs)
    {
        return Vec3d(lhs[0] / rhs[0], lhs[1] / rhs[1], lhs[2] / rhs[2]);
    }

}    // end of namespace osg

#endif
